Tissue spacer implants, insertion and adjustment tools, and method of use

ABSTRACT

Tissue spacer implants and surgical methods for inserting the implants are disclosed. The implants may include a first cylindrical body with an outer surface, an axially extending hole, and a first end, a second cylindrical body with an outer surface and an axially extending hole, and an adjustment member with an outer surface, an axial hole, and at least one helical slot. The adjustment member axial hole may be adapted to receive the first cylindrical body and the adjustment member may be configured to be inserted into the axially extending hole of second cylindrical body. The implants may also include a travel mechanism for engaging the first cylindrical body, adjustment member, and second cylindrical body along the at least one helical slot to maintain a space between two bodies of tissue.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.14/377,212 filed on Aug. 7, 2014, which is a national stage filing undersection 371 of International Application No. PCT/US2013/025134 filed onFeb. 7, 2013 and published in English on Aug. 15, 2013 as WO2013/119803, which claims priority benefit under 35 U.S.C. §119(e) ofU.S. provisional application No. 61/595,755 filed Feb. 7, 2012, whichare incorporated herein by reference in their entireties.

TECHNICAL FIELD

The present invention relates generally to general surgery, orthopaedicand neurosurgical implants used for insertion within a space betweenhard and soft tissue structures, and more specifically, but notexclusively, concerns devices implanted within a bone to replace aresected, fractured or diseased portion and to maintain or reestablishproper spacing between the bone fragments.

BACKGROUND OF THE INVENTION

Damage or disease that affects the integral structure of a bone or otherstructures, may lead to neurologic impairment or loss of structuralsupport integrity with possible permanent damage to the surrounding softtissue and adjacent neurologic, vascular and systemic structures.Maintaining or reestablishing anatomic spacing within a bone structureor other structural tissue is critical to ensuring continuedfunctionality and mobility of the patient and avoidance of long-termserious neurological, vascular or other systemic impairments. Pleasenote that the terms “implant” and “device” may be used interchangeablyand have the same meaning herein.

SUMMARY OF THE INVENTION

Advancement of the state of tissue spacer devices and implants and thesurgical management relating to the clinical presentation of missing ordamaged bone fragments and other hard/soft tissue structures within thebody is believed desirable. One example of an embodiment of theinvention that satisfies the need for improvements to a tissue spacerdevice used to treat patients suffering from either diseased or damagedbone or other tissue structures includes a first cylindrical body, asecond cylindrical body, an adjustment member, an end member, and atravel mechanism.

The present invention provides in one aspect, a tissue spacer implantincluding a first cylindrical body with an outer surface, an axiallyextending hole, and a first end and a second cylindrical body with anouter surface and an axially extending hole. The implant may alsoinclude an adjustment member with an outer surface, an axial holeextending from a first end to a second end, and at least one diagonalslot extending partially around the outer surface of the adjustmentmember. The axial hole of the adjustment member is adapted to receivethe first cylindrical body and the adjustment member is configured to beinserted into the axially extending hole of the second cylindrical body.In addition, the implant may include a first travel mechanism forengaging the first cylindrical body, the adjustment member, and thesecond cylindrical body along the at least one diagonal slot of theadjustment member to maintain a space between two bodies of tissue.

The present invention provides in another aspect, a tissue spacerimplant including at least one inner cylindrical body with an outersurface, an axially extending hole, and a first end and an outercylindrical body with an outer surface and an axially extending hole.The implant may also include at least one adjustment member with anouter surface, an axially extending hole, and at least one helical slotaround the outer surface of the at least one adjustment member. Theaxially extending hole of the at least one adjustment member is adaptedto receive the outer surface of the at least one inner cylindrical bodyand the outer surface of the at least one adjustment member is adaptedto be inserted into the axially extending hole of the outer cylindricalbody. In addition, the implant may include at least one travelmechanism. The at least one travel mechanism may include a shaft, theshaft may pass through the at least one inner cylindrical body, the atleast one adjustment member, and the outer cylindrical body to maintaina desired position along the at least one helical slot of the at leastone adjustment member.

The present invention provides in yet another aspect, a surgical methodfor maintaining a space between two tissue bodies in a living being. Themethod may include the step of obtaining a medical device that has afirst cylindrical body that includes an outer surface, an axiallyextending hole, and a first end. The medical device includes a secondcylindrical body with an outer surface and an axially extending hole.The medical device also includes an adjustment member with an outersurface, an axial hole extending from a first end to a second end, andat least one helical slot extending partially around the outer surfaceof the adjustment member. The axial hole of the adjustment member isadapted to receive the first cylindrical body and the adjustment memberis configured to be inserted into the axially extending hole of thesecond cylindrical body. In addition, the medical device may alsoinclude a first travel mechanism engaging the first cylindrical body,the adjustment member, and the second cylindrical body along the atleast one helical slot of the adjustment member to maintain a spacebetween two bodies of tissue. The method may further include the step ofcoupling the second cylindrical body of the medical device to a tool.The method may also include the step of positioning and inserting thetool with the medical device in a retracted position into a spacebetween the two tissue bodies to maintain or increase the spacetherebetween. The method may also include the further step of adjustingthe medical device along the at least one helical slot of the adjustmentmember to a desired length. The method typically further includes thestep of securing the first cylindrical body, the adjustment member, andthe second cylindrical body using a locking mechanism at a desiredlength.

Further, additional features and advantages are realized through thetechniques of the present invention. Other embodiments and aspects ofthe invention are described in detail herein and are considered a partof the claimed invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter which is regarded as the invention is particularlypointed out and distinctly claimed in the claims at the conclusion ofthe specification. It is emphasized that, in accordance with thestandard practice in the industry, various features are not drawn toscale. In fact, the dimensions of the various features may bearbitrarily increased or reduced for clarity of discussion. Theforegoing and other objects, features and advantages of the inventionare apparent from the following detailed description taken inconjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of one embodiment of a tissue spacer devicein a retracted position, in accordance with an aspect of the presentinvention;

FIG. 2 is a front view of the tissue spacer device of FIG. 1, inaccordance with an aspect of the present invention;

FIG. 3 is a side view of the tissue spacer device of FIG. 1 with a toolinserted into the tissue spacer device, in accordance with an aspect ofthe present invention;

FIG. 4 is a top view of the tissue spacer device of FIG. 1 and the toolof FIG. 3, in accordance with an aspect of the present invention;

FIG. 5 is a bottom view of the tissue spacer device of FIG. 1 and thetool of FIG. 3, in accordance with an aspect of the present invention;

FIG. 6 is a perspective view of the tissue spacer device of FIG. 1 in afully extended position and the tool of FIG. 3, in accordance with anaspect of the present invention;

FIG. 7 is a partially exploded side, perspective view of the tissuespacer device of FIG. 1 and the tool of FIG. 3, in accordance with anaspect of the present invention;

FIG. 8 is a partially exploded front, perspective view of the tissuespacer device of FIG. 1 and the tool of FIG. 3, in accordance with anaspect of the present invention;

FIG. 9 is a partially exploded perspective view of the tissue spacerdevice of FIG. 1 and the tool of FIG. 3, in accordance with an aspect ofthe present invention;

FIG. 10 is a fully exploded side, perspective view of the tissue spacerdevice of FIG. 1, in accordance with an aspect of the present invention;

FIG. 11 is a fully exploded back, perspective view of the tissue spacerdevice of FIG. 1, in accordance with an aspect of the present invention;

FIG. 12 is a cross sectional view of the device shown in FIG. 4 asviewed along section line 12-12 in FIG. 4, in accordance with an aspectof the present invention;

FIG. 13 is a cross sectional view of the device shown in FIG. 3 asviewed along section line 13-13 in FIG. 3, in accordance with an aspectof the present invention;

FIG. 14 is a cross sectional view of the device shown in FIG. 3 asviewed along section line 14-14 in FIG. 3, in accordance with an aspectof the present invention;

FIG. 15 is a perspective view of another alternative embodiment of atissue spacer device in a retracted position with a tool inserted intothe tissue spacer device, in accordance with an aspect of the presentinvention;

FIG. 16 is a perspective view of the tissue spacer device of FIG. 15 ina fully expanded position and the tool of FIG. 15, in accordance with anaspect of the present invention;

FIG. 17 is a bottom perspective view of the tissue spacer device of FIG.15 in a fully expanded position and the tool of FIG. 15, in accordancewith an aspect of the present invention;

FIG. 18 is a fully exploded top perspective view of the tissue spacerdevice and tool of FIG. 15, in accordance with an aspect of the presentinvention;

FIG. 19 is a fully exploded bottom perspective view of the tissue spacerdevice and tool of FIG. 15, in accordance with an aspect of the presentinvention;

FIG. 20 is a top view of the tissue spacer device and the tool of FIG.15, in accordance with an aspect of the present invention;

FIG. 21 is a cross sectional view of the device shown in FIG. 15 asviewed along section lines 21-21 in FIG. 20, in accordance with anaspect of the present invention;

FIG. 22 is a cross sectional view of the device shown in FIG. 15 asviewed along section lines 22-22 in FIG. 20, in accordance with anaspect of the present invention;

FIG. 23 is a perspective view of yet another alternative embodiment of atissue spacer device in a retracted position, in accordance with anaspect of the present invention;

FIG. 24 is a fully exploded top perspective view of the tissue spacerdevice of FIG. 23, in accordance with an aspect of the presentinvention;

FIG. 25 is a perspective view of another embodiment of a tissue spacerdevice and a tool inserted into the tissue spacer device, in accordancewith an aspect of the present invention;

FIG. 26 is a perspective view of the tissue spacer device of FIG. 25 ina fully expanded position and the tool of FIG. 25, in accordance with anaspect of the present invention;

FIG. 27 is a fully exploded top perspective view of the tissue spacerdevice and tool of FIG. 25, in accordance with an aspect of the presentinvention;

FIG. 28 is a fully exploded bottom perspective view of the tissue spacerdevice and tool of FIG. 25, in accordance with an aspect of the presentinvention;

FIG. 29 is a top view of the tissue spacer device and tool of FIG. 25,in accordance with an aspect of the present invention;

FIG. 30 is a cross sectional view of the device shown in FIG. 25 asviewed along section lines 30-30 in FIG. 29, in accordance with anaspect of the present invention;

FIG. 31 is a cross sectional view of the device shown in FIG. 25 asviewed along section lines 31-31 in FIG. 29, in accordance with anaspect of the present invention;

FIG. 32 is a perspective view of an insertion tool and lockinginstrument engaging the tissue spacer device of FIG. 1, in accordancewith an aspect of the present invention;

FIG. 33 is a partially exploded, perspective view of the insertion tooland locking instrument of FIG. 32 and the tissue spacer device of FIG.1, in accordance with an aspect of the present invention;

FIG. 34 is a truncated perspective view of the insertion tool andlocking instrument of FIG. 32 and the tissue spacer device of FIG. 1, inaccordance with an aspect of the present invention;

FIG. 35 is an exploded perspective view of the insertion tool of FIG.32, in accordance with an aspect of the present invention;

FIG. 36 is a perspective view of the insertion tool of FIG. 32 with atransparent handle, outer housing and knob, in accordance with an aspectof the present invention;

FIG. 37 depicts one embodiment of a surgical method for implanting atissue spacer device into a patient's body, in accordance with an aspectof the present invention;

FIG. 38 is a perspective view of a travel mechanism for a tissue spacerimplant, in accordance with an aspect of the present invention;

FIG. 39 is a perspective view of another travel mechanism for a tissuespacer implant, in accordance with an aspect of the present invention;

FIG. 40 is a side view of a locking mechanism inserter, in accordancewith an aspect of the present invention;

FIG. 41 is a side view of an alternative locking mechanism inserter, inaccordance with an aspect of the present invention;

FIG. 42 a truncated perspective view of the engagement end of thelocking mechanism inserter of FIG. 38, in accordance with an aspect ofthe present invention;

FIG. 43 a truncated perspective view of the engagement end of thelocking mechanism inserter of FIG. 39, in accordance with an aspect ofthe present invention;

FIG. 44 is a fully exploded side, perspective view of an alternativetissue spacer device, in accordance with an aspect of the presentinvention; and

FIG. 45 is a fully exploded side, perspective view of anotheralternative tissue spacer device, in accordance with an aspect of thepresent invention.

DETAILED DESCRIPTION FOR CARRYING OUT THE INVENTION

Generally stated, disclosed herein are tissue spacer implants, anadjustment tool, and an insertion tool. As used herein, the terms“tissue spacer implant,” “implant,” “medical device,” and “device” maybe used interchangeably as they essentially describe the same type ofdevice. Surgical methods for implanting the tissue spacer implants arealso disclosed.

As shown in FIG. 1, the general arrangement of a tissue spacer implant10, in accordance with an aspect of the present invention, may include acylindrical body or post-like member. The implant 10 as shown in FIGS.1-6 has, for example, a generally circular cross-sectional geometry,although it is contemplated that other geometric or anatomical shapesmay also be used in the construct. The implant 10 may likely include anend member 20, an outer cylindrical body 30, an intermediate adjustmentmember 40, and an inner cylindrical body 50. The implant 10 may alsoinclude a fastener 110. The intermediate adjustment member 40 isdetachably coupled to the inner cylindrical body or first cylindricalbody 50 and the outer cylindrical body or second cylindrical body 30.The terms “inner cylindrical body” and “first cylindrical body” may beused interchangeably as they have essentially the same meaning herein.Likewise, the terms “outer cylindrical body” and “second cylindricalbody” may be used interchangeably as they have essentially the samemeaning herein. In addition, the terms “intermediate adjustment member”and “adjustment member” may be used interchangeably as they haveessentially the same meaning herein. The end member 20 is detachablycoupled to the inner cylindrical body 50 and the fastener 110 may beused to detachably couple the end member 20 to the inner cylindricalbody 50.

As seen in FIGS. 10-11, the end member 20 typically includes a first end22 and second end 24, the outer cylindrical body 30 typically includes afirst end 32 and second end 34, the intermediate adjustment member 40typically includes a first or superior end 42 and second or inferior end44, and the inner cylindrical body 50 typically includes a first end 52and second end 54. The first end 22 of the end member 20 beingconfigured to provide a bone contacting surface and the second end 24being configured to couple to the first end 52 of the inner cylindricalbody 50. The fastener 110 may be used to secure the end member 20 to theinner cylindrical body 50. The second end 54 of the inner cylindricalbody 50 may be configured to couple to the first end 42 of theintermediate adjustment member 40. The second end 44 of the intermediateadjustment member 40 may be configured to couple with the first end 32of the outer cylindrical body 30 and for mating with a tool, forexample, adjustment mechanism 60 or the positioning mechanism 440 of theinsertion tool 400. The terms “adjustment mechanism,” “tool,”“adjustment tool,” and “instrument” may be used interchangeably hereinas they essentially refer to the same device. The second end 34 of theouter cylindrical body 30 may be configured to provide a bone contactingsurface 102. As shown in FIGS. 13-14, the outer cylindrical body 30,intermediate adjustment member 40, and inner cylindrical body 50 may,for example, have a circular cross sectional shape, but other polygonalor anatomical shapes may be used.

The end member 20 may also be hollow or include a central bore 26 thatpasses from the first end 22 to the second end 24. The central bore 26may be filled with bone graft material post-implantation. The first end22 may include a ridged contact surface with a plurality of openings 28,as seen in FIGS. 1 and 4, the disclosed embodiment includes, forexample, eight openings, which may be threaded. As best seen in FIG. 1,one or more threaded spikes 100 may be inserted into the plurality ofopenings 28. The threaded spikes 100 may be used to fasten the endmember 20 to the inner cylindrical body 50, as well as to provideadditional contact with the adjacent vertebral body. It should beunderstood by one skilled in the art that it is contemplated thatmodular end surfaces or end members 20 may be used to provide forvarying types of bone contacting surfaces and structures, including, butnot limited to sharp tines, porous coatings, biomaterial/ingrowthsurfaces, and teeth-like structures. End member 20 may also includeteeth-like structures 102 as depicted in FIGS. 1-3. Although not shown,it is also understood that alternative modular end surfaces or angledend surfaces may be attached to the end member 20 using many differentcoupling mechanisms including, but not limited to, snap locks, screws,pins, etc., to address various clinical deformities. The end member 20also includes a second end 24 including an inner ring 29 that mates withthe rim 57 on the first end 52 of the inner cylindrical body 50. Asshown, the end member 20 has a generally circular cross-sectionalgeometry, although it is contemplated that various cross-sectionalgeometries could be used in the construct depending upon the anatomicsituation and clinical application.

As seen in FIGS. 9-11, the inner cylindrical body 50 may include a rim57 or teeth-like structures (not shown) around the first end 52 formating with end member 20. The inner cylindrical body 50 also hasparallel cutouts 56 in the second end 54 to provide clearance for atool, for example, the adjustment tool 60 or positioning mechanism 440of the insertion tool 400, when it is inserted into the implant 10. Inthe depicted embodiment of FIGS. 10-11, the cutouts 56 are configured ashalf circles, although many other geometric shapes are contemplated andthe shapes shown here are for example purposes only. Above the cutouts56 are two parallel holes or openings 58 which may mate with the travelmechanism 80 to secure the intermediate adjustment member 40 at adesired separation. Also along the inner cylindrical body 50 between thefirst end 52 and the second end 54 there may be a plurality of elongatedvertically oriented openings 59 passing through the outer surface intothe central cavity 51. The elongated vertically oriented openings 59 maybe oval in shape, as seen in FIGS. 10 and 11, although many othergeometric shapes are contemplated and the shapes shown are for examplepurposes only. The first end 52 of the central cavity may includeinterior threads 53 for engaging the threaded end 114 of the fastener110, as seen in FIG. 10.

As shown in FIGS. 9-11, the intermediate adjustment member 40 mayinclude two diagonal or helical openings 46 between the first end 42 andthe second end 44 passing through the outer surface into the centralcavity 41. The diagonal openings 46 are angled from the first end 42towards the second end 44, although other alignment angles arecontemplated. As seen in FIGS. 10 and 11, the openings 46 are slots,although many other geometric shapes are contemplated and the shapesshown are for example purposes only. The openings 46 may includedepressions 47 along the inside of the openings 46 to provide indentsfor the shaft 86 of the travel mechanism 80 to sit in at the variousadjustment heights. However, the openings 46 may also have smooth wallswith any incremental changes of height being controlled and determinedby the spacing of the gears 48 on the adjustment member 40. The secondend 44 of the intermediate adjustment member 40 may include teeth-likeor gear structures 48 for mating with a tool, for example, theadjustment tool 60 or insertion tool 400.

Continuing to refer to FIGS. 9-11, the outer cylindrical body 30 mayinclude a plurality of vertical or oblong openings 36 along the outersurface that extend between the first end 32 and the second end 34passing through the outer surface and into the central cavity 31. Thevertical openings 36 as seen in FIGS. 10 and 11, may be oval in shape,although many other geometric shapes are contemplated and the shapesshown are for example purposes only. At least one of the plurality ofvertical openings 36 may be shorter than the remaining plurality ofvertical openings 36 where the adjustment opening 38 is located near thesecond end 34 of the outer cylindrical body 30. The adjustment opening38 and shorter vertical opening 36 extend from the central cavity 31 tothe exterior of the cylindrical body 30 through an engagement boss 33.The engagement boss 33 extends out from the exterior surface of thecylindrical body 30 at an angle to create a surface for a tool, forexample, insertion tool 400, to engage the implant 10 during insertionand adjustment in the patient. The bottom surface 39 of the second end34 being configured to provide a bone contacting surface and having aridged contact surface. It should be understood by one skilled in theart that it is contemplated that the second end 34 of the outercylindrical body 30 may have varying types of bone contacting surfacesand structures, including, but not limited to sharp tines, porouscoatings, biomaterial/ingrowth surfaces, and teeth-like structures 102,as seen in FIGS. 1, 2, 10 and 11. The outer cylindrical body 30 may alsoinclude an interior rim 35, as shown in FIGS. 10 and 12. The interiorrim 35 may have a gap where the interior rim 35 intersects with theadjustment opening 38 to enable an adjustment mechanism or tool to beinserted into the adjustment opening 38. The interior rim 35 engages thesecond end 44 of the intermediate adjustment member 40 and maintains theintermediate adjustment member 40 between the interior rim 35 and thesupport means 90 within the outer cylindrical body 30. The outercylindrical bodies 230 and 330, described in greater detail below, mayalso include at least one interior rim, such as interior rim 35, tomaintain the intermediate adjustment members 240, 340 within the outercylindrical bodies 230 and 330.

As seen in the exploded view of FIG. 9, the intermediate adjustmentmember 40 is positioned above the inner cylindrical body 50. A supportmeans 90, for example, a washer may be positioned adjacent the first end52 of the inner cylindrical body 50 prior to inserting the intermediateadjustment member 40 over the second end 54 and the body 50. The endmember 20 may then be secured to the inner cylindrical body 50 using thefastener 110. As seen in FIGS. 9 and 12 the outer cylindrical body 30may then be positioned over the intermediate adjustment member 40 andthe support member 90 may be inserted into the channel 37 in the outercylindrical body 30.

As seen in the sectional views of FIGS. 12-14, a channel 92 is createdby the combination of two parallel vertical openings 36 of the outercylindrical body 30 being aligned with the openings 46 of the adjustmentmember 40 and the two parallel holes 58 of the inner cylindrical member50. A shaft 86 of the travel mechanism 80 may be inserted into thechannel 92. As shown in FIG. 38, the shaft 86 may include a first end 94and a second end 96. The first end 94 may, for example, include a headportion 82 and the second end 96 may, for example, include a threadedportion 88. The head portion 82 of the travel mechanism 80 may mate withone of the parallel vertical openings 36 of the outer cylindrical body30 and the threaded portion 88 exiting the parallel opening 36 of thebody 30. The threaded portion 88 may mate with an engagement member 84,such as a nut. An optional washer (not shown) may be inserted over thesecond end 96 prior to attaching the engagement member 84 onto thefastener 82. The engagement member 84 may be attached to the threadedportion 88 of the travel mechanism 80 to couple the outer cylindricalbody 30, the intermediate adjustment member 40, and the innercylindrical body 50. The engagement member 84 may not be fully tightenedto allow for rotation of the intermediate adjustment member 40. Once theimplant 10 is at a desired height, the engagement end 84 and headportion 82 of the travel mechanism 80 may be tightened together tosecure the intermediate adjustment member 40 in position and with theinner cylindrical body 50 at the selected height. Alternative means forsecuring the outer cylindrical body 30, the intermediate adjustmentmember 40, and the inner cylindrical body 50 at a desired height arediscussed in greater detail below.

As seen in FIGS. 1 and 6, respectively, the implant 10 is in the fullyretracted position and fully extended position. In order to adjust theheight of the implant 10, a tool, for example, an adjustment tool 60 orpositioning mechanism 440 of the insertion tool 400, may be insertedinto opening 38, as shown in FIGS. 8 and 32. The adjustment tool 60 mayinclude a guide pin 62, a plurality of gear teeth 64, a handle 66 and aconnector rod 68, as shown in FIGS. 7 and 9. The connector rod 68 islocated intermediate and connects the guide pin 62 and the handle 66.The gear teeth 64 being located at the point where the connector rod 68meets the guide pin 62. The insertion tool 400 is described in greaterdetail below.

As seen in FIG. 14, when the guide pin 62 is inserted into opening 38,it passes under the adjustment member 40 and the cutouts 56 of the innercylindrical body 50. Once the adjustment tool 60 is completely insertedinto the opening 38, the gear teeth 64 of the adjustment tool 60interface with the teeth-like or gear structures 48 of the adjustmentmember 40. As the handle 66 is rotated the gear teeth 64 mate with theteeth-like or gear structures 48 to rotate the intermediate adjustmentmember 40. As the intermediate adjustment member 40 turns it causes thefixed travel mechanism 80 to slide along the path of the diagonalopenings 46. Since the travel mechanism 80 is coupled to the innercylindrical body 50, as the travel mechanism 80 moves along the diagonalslots 46 the inner cylindrical body 50 moves either upward or downwarddepending on the direction of rotation. The end member 20 may move awayor move towards the first end 32 of the outer body 30 either lengtheningor shortening the height of the implant 10, as seen in FIGS. 6-8.

Referring now to FIGS. 15-22, an alternative embodiment implant 200,similar to the implant 10 as described above, but includes a secondfastener 210 and a second end member 220. The first end member 20, outercylindrical body 230, intermediate adjustment member 240, innercylindrical body 250, travel mechanism 80, washer 90, and fastener 110are similar to those described above with reference to FIGS. 1-14. Asseen in FIG. 16, the intermediate adjustment member 240 is detachablycoupled to the inner cylindrical body or first cylindrical body 250 andthe elongated outer cylindrical body or second cylindrical body 230, asdescribed above with reference to FIGS. 1-14. The first end member 20may be detachably coupled to the inner cylindrical body 250 with thefastener 110 and the second end member 220 may be detachably coupled tothe elongated outer cylindrical body 230 with a second fastener 210. Thefirst and second end members 20, 220 each having at least one threadedspike 100 and teeth-like structures 102 on the bone contact surface forengagement with the patient's bone, as shown in FIGS. 16-18. Theadjustment tool 60 is of the type described above with reference toimplant 10. For brevity sake the functionality and element relationshipswill not be restated here, but it is understood that they include all ofthe same limitations of and function in the same manner as implant 10,other than addition of the second end member 220.

As seen in FIGS. 15 and 16, respectively, the implant 200 is in thefully retracted position and fully extended position and is adjusted asdescribed above with reference to FIGS. 1-14. The implant 200 may comein a variety of sizes, wherein the diameter and length of the outercylindrical body 230, intermediate adjustment member 240, and innercylindrical body 250 vary depending on the size of the desired implant.As shown in FIGS. 15-19, for example, the outer cylindrical body 230,intermediate adjustment member 240, and inner cylindrical body 250 maybe elongated. Referring now to FIGS. 23-24, the outer cylindrical body230, intermediate adjustment member 240, and inner cylindrical body 250may be shorter in length, thus the height of the implant 200 shown inFIGS. 23 and 24 is less than the height of the implant 200 shown inFIGS. 15-22.

Another alternative embodiment implant 300 is depicted in FIGS. 25-31,the implant 300 including an elongated outer cylindrical body or secondcylindrical body 330 to accommodate a first or superior innercylindrical body 250 and second or inferior inner cylindrical body 350coupled to a first and second intermediate adjustment member 240, 340,respectively. The terms “second inner cylindrical body,” “inferior innercylindrical body,” and “third cylindrical body” may be usedinterchangeably as they have essentially the same meaning herein. Theintermediate adjustment members 240, 340 are of the type described abovewith reference to the intermediate adjustment member 40 of implant 10depicted in FIGS. 1-14. The first inner cylindrical body 250 may also becoupled to a first end member 20 with the first fastener 110 and thesecond inner cylindrical body 350 may also be coupled to a second endmember 220 with the second fastener 210. The end members 210, 220 havingthe same limitations and functionality as those described above withreference to the implant 200 depicted in FIGS. 15-22.

As seen in FIGS. 25 and 26, respectively, the implant 300 is in thefully retracted position and fully extended position. In order to adjustthe height of the implant 300 a tool, for example, the adjustment tool60 or insertion tool 400, may be inserted into opening 338, shown inFIG. 27. The adjustment tool 60 including a guide pin 62, a plurality ofgear teeth 64, a handle 66 and a connector rod 68, as described abovewith reference to FIGS. 3-7. The connector rod 68 is locatedintermediate and connects the guide pin 62 and the handle 66. The gearteeth 64 being located at the point where the connector rod 68 meets theguide pin 62. The insertion tool 400 will be discussed in greater detailbelow.

As seen in the sectional views of FIGS. 30 and 31, when the guide pin 62is inserted into opening 338 it passes between the adjustment members240 and 340 and the cutouts 256 and 356 of the inner cylindrical bodies250 and 350. Once the adjustment tool 60 is completely inserted into theopening 338, the gear teeth 64 of the adjustment tool 60 interface withthe teeth-like or gear structures 248 and 348 of the adjustment members240 and 340, respectively. As the handle 66 is rotated the gear teeth 64mate with the teeth-like or gear structures 248 and 348 to rotate theadjustment members 240 and 340, respectively. The adjustment members 240and 340 will turn in opposite directions as they rotate when thesuperior travel mechanism 80 is inserted into the lowest point of thediagonal slots 246 on the second end 244 of the adjustment member 240and the inferior travel mechanism 80 is inserted into the highest pointof the diagonal slots 346 on the second end 344 of the adjustment member340. As the intermediate adjustment members 240, 340 turn they cause thesuperior and inferior fixed travel mechanisms 80 to slide along thepaths of the diagonal openings 246, 346. As the travel mechanisms 80move along the diagonal slots 246, 346 the inner cylindrical bodies 250,350 moves either upward or downward depending on the direction ofrotation, because the travel mechanisms 80 are coupled to the innercylindrical bodies 250, 350. The end member 20 may move away or movetowards the first end 332 of the outer body 330 and the opposing endmember 220 may also move away or move towards the second end 334 of theouter body 330, either lengthening or shortening the implant 300, asshown in FIGS. 25 and 26.

The appropriate surgical exposure and dissection techniques for theexample surgical method using the tissue spacer implant 10, 200 or 300are well known in the art. As shown in FIG. 37, the surgical method forusing the implant 10, 200 or 300 may include the step 500 of obtaining aproperly sized and configured implant 10, 200, or 300. The method mayalso include assembling the implant 10, 200, or 300 by selecting an endmember 20 and attaching the selected end member 20 to the innercylindrical body 50, 250. The assembling step may further includeselecting a fastener 110 and inserting the fastener 110 through theopening 26 in the end member 20 and into the central cavity 51, 251 ofthe inner cylindrical body 50, 250 to engage the threads 53, 253. Ifimplant 200 is being used, the assembly step may also include selectinga second end member 220 and attaching the selected second end member 220to the second end 234 of the elongated cylindrical body 230. Theassembling step for implant 200 may also include selecting a secondfastener 210 and inserting the second fastener 210 through the opening226 in the second end member 220 and into the central cavity 231 toengage the inner threads 235 of the elongated cylindrical body 230. Ifthe implant 300 is being used, the assembly step may also includeselecting a second end member 220 and attaching the selected second endmember 220 to the second inner cylindrical body 250. The assembling stepfor implant 300 may further include selecting a second fastener 210 andinserting the second fastener 210 through the opening 226 in the endmember 220 and into the central cavity 351 of the inner cylindrical body350 to engage the threads 353.

Once the tissue spacer implant 10, 200, or 300 is assembled, the nextstep 502 may include attaching the tissue spacer implant 10, 200, or 300to an insertion tool, for example, insertion tool 400 described ingreater detail below. Following the attachment of the tissue spacerimplant 10, 200, or 300 to the insertion tool 400, the next step 504includes placing the implant 10, 200 or 300 between two tissue bodies.For example purposes only, we shall describe herein the technique asused in the replacement of a missing vertebral body. The end of theinsertion tool 400 with the coupled and aligned implant 10, 200 or 300is positioned within a space within a spinal column. If implant 10 isused the end member 20 and outer cylindrical body 30 may be positionedto engage respective adjacent vertebral bodies. Alternatively, ifimplant 200 or 300 is used the end member 20 and the second end member220 may be positioned to engage respective adjacent vertebral bodies. Anadjustment tool 60 may then be used during step 506 to complete thedistraction step or maintenance of the existing space by lengthening orshortening the implant 10, 200, or 300, as described above, to thedesired height to enable the end member 20 and the outer cylindricalbody 30 or first and second end members 20, 220 to sufficiently engagethe respective adjacent vertebral bodies. The positioning mechanism 440of the insertion tool 400 may alternatively be used in place of theadjustment tool 60 in the currently described methods, as described ingreater detail below. Once the desired length is achieved, step 508 mayinclude securing a travel mechanism 80 before or after a tool, forexample, the adjustment tool 60, is removed to prevent rotationalmovement of the intermediate adjustment member 40, 240, 340. If theadjustment tool 60 is removed prior to fixing the travel mechanism 80,once the travel mechanism 80 is secured, the implant 10, 200, 300 isfixed at the required length to maintain the necessary space between thetwo vertebral bodies. The travel mechanism 80 may be tightened to fixthe implant 10, 200, or 300 at a desired height. If the adjustment tool60 is removed after securing the travel mechanism 80, the method mayfurther include the step of fixing the travel mechanism 80 onto theouter cylindrical body 30, 230, 330 and securing the intermediateadjustment member 40, 240, 340 in position between the outer cylindricalbody 30, 230, 330 and the inner cylindrical body 50, 250, 350, to securethe implant 10, 200, 300 at a desired height between two vertebralbodies within a patient's spinal column. The method may further includethe step of removing the adjustment tool 60 or insertion tool 400 fromthe outer cylindrical body 30, 230, 330 of the implant 10, 200, 300 andremoving the adjustment tool 60 from inside the living body.

It should be understood by those skilled in the art that the surgicalmethod described herein may also include using alternative embodimentsof end members 20, 220 to accommodate various clinical deformities orbone growth coatings.

Referring now to FIGS. 32-36, an alternative insertion tool 400 andlocking instrument 470 are shown. The insertion tool 400 and lockinginstrument 470 engaging the implant 10 is shown in FIG. 32. Theinsertion tool 400 includes a handle 402 coupled to a housing 430 whichmay receive a positioning mechanism 440 and an insertion mechanism 450.The handle 402 may include a proximal handle portion 404 and a distalhandle portion 406. The distal handle portion 406 may have a firstopening 408 along the longitudinal axis of the handle 402 for receivingthe proximal handle portion 404. The proximal handle portion 404 may besecured to the distal handle portion 406 using fasteners, for example,screws (not shown). The distal handle portion 406 may also include asecond opening 410 along the longitudinal axis of the handle 402 andopposite the first opening 408 for receiving the housing 430 and theinsertion mechanism 450. The proximal handle portion 404 may have athrough hole 412 along the longitudinal axis of the handle 402 forreceiving the positioning mechanism 440 and engaging the insertionmechanism 450 at a distal end of the through hole 412 of the proximalhandle portion 404. The proximal handle portion 404 may also include anopening 414 perpendicular to and engaging the through hole 412. Theopening 414 is configured to receive the actuation button 420.

Referring now to FIG. 36, the actuation button 420 may include two sidechannels 422 that engage fasteners for securing the actuation button 420to the handle 402 and the two side channels 422 are configured to enablethe fasteners to slide along the channels 422 allowing the actuationbutton 420 to move. The actuation button 420 may also include an opening424 with a locking channel 426 for securing the positioning mechanism440 in the handle 402 of the insertion tool 400. As seen in FIGS. 34-36,the positioning mechanism 440 may include a shaft 442 with a channel 444at the proximal end of the shaft 442 for engaging the opening 424 andlocking channel 426 of the actuation button 420. The positioningmechanism 440 may also include a knob 446 which couples to the proximalend of the shaft 442. The shaft 442 of the positioning mechanism 440 mayalso include a plurality of gear teeth 448 at the distal end of theshaft 442. The plurality of gear teeth 448 of the shaft 442 of thepositioning mechanism 440 are configured to engage the teeth-like orgear structures 48 of the intermediate adjustment mechanism 40 of theimplant 10.

The positioning mechanism 440 may pass through the handle 402 and thenthrough the insertion mechanism 450 to enable engagement with theadjustment mechanism 40 of the implant 10. The insertion mechanism 450may include a proximal end 452 and a distal end 454 as shown in FIG. 35.The distal end 454 may include a threaded end 460 for engagingcorresponding threads within the distal end of the through hole 412 ofthe proximal handle portion 406. As shown in FIG. 34, the insertionmechanism 450 may also include a through opening 458 running along thelongitudinal axis of the insertion mechanism 450. The shaft 442 of thepositioning mechanism 440 may pass through the through opening 458 ofthe insertion mechanism 450. The insertion mechanism 450 may furtherinclude an engagement channel 456 on the proximal end 452 of theinsertion mechanism 450 for mating with the engagement boss 33 on theexterior surface of the outer cylindrical body 30 of the implant 10, asshown in FIG. 32.

The insertion mechanism 450 may fit within the housing 430 of theinsertion tool 400 as shown in FIG. 36. The housing 430 may include aproximal end 432 that couples to the distal handle portion 406 and adistal end 434, as shown in FIG. 35. The housing 430 may be secured tothe distal handle portion 406 using fasteners, for example, screws (notshown). The housing 430 may also include a through hole 436 passing fromthe proximal end 432 to the distal end 434 along the longitudinal axisof the housing 430. The insertion mechanism 450 may be inserted into thethrough hole 436 from the distal end 434 of the housing 430 and pass outof the housing 430 at the proximal end 432 to engage the proximal handleportion 404. Once the housing 430 and insertion mechanism 450 arecoupled to the handle 402, the engagement channel 456 of the insertionmechanism 450 of the insertion tool 400 may be attached to theengagement boss 33 on the outer cylindrical body 30 of the implant 10.

The locking instrument 470 may include a shaft 472 with a proximal end474 and a distal end 476, as seen in FIGS. 32-34. The locking instrument470 may include a knob 478 at the proximal end 474 of the shaft 472 foradjusting the travel mechanism 80 of the implant 10. The lockinginstrument 470 may also include an engagement end 480 at the distal end476 of the shaft 472. The engagement end 480 may be configured to engagethe head portion 82 of the travel mechanism 80. The engagement end 480may include a head that enables rotation of the head portion 82 of thetravel mechanism 80 at an angle, as shown in FIG. 32, to enable the useof the insertion tool 400 and the locking instrument 470 simultaneously.The engagement end 480 may, for example, have a hexagon, square, orother multi-lobed configuration allowing the engagement end 480 toengage the head portion 82 to tighten the travel mechanism 80 andengagement member 84 to secure the implant 10 in the desire extension orretraction.

The insertion tool 400 and locking instrument 470 may also be used inthe above described surgical method in place of the adjustment tool 60.Prior to inserting the positioning mechanism 440, the insertion tool 400may be secured to the implant 10 by sliding the engagement boss 33 ofthe implant 10 into engagement with the engagement channel 456 of theinsertion mechanism 450. Next, the positioning mechanism 440 may beinserted into the handle 402 of the insertion tool 400 and slid throughthe insertion mechanism 450 inside the housing 430 of the insertion tool400 to engage the plurality of gear teeth 448 of the shaft 442 of thepositioning mechanism 440 with the teeth-like or gear structures 48 ofthe intermediate adjustment mechanism 40 of the implant 10. Once theimplant 10 is secured to the insertion tool 400, the implant 10 may beinserted into the patient between two vertebrae. After inserting theimplant 10, the physician may adjust the height of the implant 10 byrotating the knob 446 of the positioning mechanism 440 thereby rotatingthe gear teeth 448 which are engaging the teeth-like or gear structures48 of the adjustment mechanism 40 to rotate the intermediate adjustmentmechanism 40. As the adjustment mechanism 40 turns, the fixed travelmechanism 80 slides along the path of the diagonal openings 46 causingthe coupled inner cylindrical body 50 to move in an upward or downwarddirection depending on the direction of rotation of the gear teeth 448.When a desired length of the implant 10 is achieved, the engagement end480 of the locking instrument 470 may be inserted to engage thecorresponding opening in the fastener 82 of the travel mechanism 80 totighten the travel mechanism 80 thereby securing the intermediateadjustment member 40 to the outer cylindrical body 30 and innercylindrical body 50 to prevent additional rotation of the adjustmentmember 40. After the implant 10 has been secured in the desiredposition, the locking instrument 470 may be removed from the patient andthe positioning mechanism 440 may be removed from the insertion tool400. Next the insertion tool 400 may be slid to disengage the engagementchannel 456 of the insertion mechanism 450 from the engagement boss 33of the implant 10 and the insertion tool 400 may be removed from thepatient. The patient's incision may then be closed.

Referring now to FIGS. 40 and 42, a first locking mechanism inserter 490is shown. The locking mechanism inserter 490 may include a shaft 492with an engagement end 494 at a first end and a knob 496 at a secondend. As shown in FIG. 42, the engagement end 494 may have a shapecorresponding to the shape of an opening 512 in a first lockingmechanism 510, shown in FIG. 44. The first locking mechanism 510 may beused with an alternative embodiment tissue spacer implant 508. Theimplant 508 is similar to the implant 10 described above, however theimplant 508 includes an alternative travel mechanism 518. As shown inFIG. 39, the alternative travel mechanism 518 includes a shaft 520 witha first end 522 and a second end 524. The second end 524 of the travelmechanism 518 may be inserted through the shorter vertical opening 36 inthe outer cylindrical body 30, one of the two helical openings 46,through two parallel elongated vertically oriented openings 59, througha second of the two helical openings 46, and into a second verticalopening 36 parallel to the shorter vertical opening 36. In addition, theadjustment opening 38 in the implant 508 may include threads 16 forengaging the first locking mechanism 510. The first locking mechanism510 includes a drive opening 512, exterior threads 514, and an impactend 516. As discussed above, the drive opening 512 is shaped tocorrespond to the shape of the engagement end 494 of the inserter 490.The exterior threads 514 may engage the interior threads 16 of theadjustment opening 38. The impact end 516 is configured to engage theexterior surface of the second end 44 of the intermediate adjustmentmember 40 to prevent the adjustment member 40 from rotating.

Once the implant 508 is assembled, the implant 508 may be inserted intoa patient using the insertion tool 400. The positioning mechanism 440(see FIGS. 34-36) may be used to increase or decrease the height of theimplant 508, as described above. After the implant 508 is adjusted to adesired height, the positioning mechanism 440 may be removed from theinsertion tool 400. The physician may then attach the engagement end 494of the first locking mechanism inserter 490 to the drive opening 512 ofthe first locking mechanism 510. Once the first locking mechanism 510 iscoupled to the first inserter 490, the first inserter 490 may beinserted into the tool 400. The first inserter 490 is inserted into thehole 412 in handle 402 and through the insertion mechanism 450 to enableinsertion of the first locking mechanism 510 into the adjustment opening38 to engage the intermediate adjustment member 40. The threads 514 ofthe first locking mechanism 510 will engage the interior threads 16 ofthe opening 38 by rotating the knob 496 of the first inserter 490. Oncethe first locking mechanism 510 is inserted into the opening 38, theimpact end 516 contacts the intermediate adjustment member 40 to securethe adjustment member 40 in the selected position to maintain thedesired height of the implant 508. The first inserter 490 may then beremoved from the insertion tool 400, the insertion tool 400 may bedetached from the implant 508, and the patient closed.

A second locking mechanism inserter 500 is shown in FIGS. 41 and 43. Thesecond locking mechanism inserter 500 may include a shaft 502 with anengagement end 504 at a first end and a knob 506 at a second end. Asshown in FIG. 43, the engagement end 504 may be threaded to engage anopening 532 in a second locking mechanism 530, shown in FIG. 45. Thesecond locking mechanism 530 may be used with another alternativeembodiment tissue spacer implant 528. The implant 528 is similar to theimplant 508 with the alternative travel mechanism 518 described above,however the implant 528 includes an alternative adjustment opening 38including a lip 18. The lip 18 in the adjustment opening 38 isconfigured to engage the second locking mechanism 530. The secondlocking mechanism 530 includes an attachment opening 532 that may bethreaded, an exterior surface 534, and a plurality of gear teeth 536.The gear teeth 536 are configured to engage the teeth-like or gearstructures 48 of the intermediate adjustment member 40 to secure theadjustment member 40 to prevent additional rotation. The exteriorsurface 534 may be shaped to correspond to the shape of the adjustmentopening 38 above the lip 18.

Once the implant 528 is assembled, the implant 528 may be inserted intoa patient with the insertion tool 400. As discussed above, thepositioning mechanism 440 (see FIGS. 34-36) may be used to increase ordecrease the height of the implant 528. After the implant 528 isadjusted to a desired height, the positioning mechanism 440 may beremoved from the insertion tool 400. The physician may then attach thesecond locking mechanism 530 to the second locking mechanism inserter500 by rotating the threads of the engagement end 504 of the secondlocking mechanism 530 to engage the threads of the attachment opening532 of the second inserter 500. Once the second locking mechanism 530 issecured to the second locking mechanism inserter 500, the secondinserter 500 may be inserted into the insertion tool 400 to enableinsertion of the second locking mechanism 530 into the adjustmentopening 38 to engage the intermediate adjustment member 40. As thesecond locking mechanism 530 is inserted into the opening 38, the gearteeth 536 of the locking mechanism 530 will engage the teeth-like orgear structures 48 of the intermediate adjustment member 40 and theexterior surface 534 of the locking mechanism 530 will engage the lip 18of the adjustment opening 38 of the implant 528. The gear teeth 536 andexterior surface 534 of the second locking mechanism 530 will engage theintermediate adjustment member 40 and the adjustment opening 38 of theimplant 528 to lock the intermediate adjustment member 40 in theselected position to maintain a desired height of the implant 528. Thesecond inserter 500 may then be removed from the locking mechanism 530by rotating the knob 506 to remove the threads of the engagement end 504from the threads of the attachment opening 532 of the second lockingmechanism 530. Once the engagement end 504 of the second inserter 500 isremoved from the second locking mechanism 530, the second inserter 500may be removed from the insertion tool 400. After removing the secondinserter 500, the insertion tool 400 may be detached from the implant528 and the patient's incision closed.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprise” (andany form of comprise, such as “comprises” and “comprising”), “have” (andany form of have, such as “has”, and “having”), “include” (and any formof include, such as “includes” and “including”), and “contain” (and anyform of contain, such as “contains” and “containing”) are open-endedlinking verbs. As a result, a method or device that “comprises,” “has,”“includes,” or “contains” one or more steps or elements possesses thoseone or more steps or elements, but is not limited to possessing onlythose one or more steps or elements. Likewise, a step of a method or anelement of a device that “comprises,” “has,” “includes,” or “contains”one or more features possesses those one or more features, but is notlimited to possessing only those one or more features. Furthermore, adevice or structure that is configured in a certain way is configured inat least that way, but may also be configured in ways that are notlisted.

Although the example embodiments have been depicted and described indetail herein, it will be apparent to those skilled in the relevant artthat various modifications, additions and substitutions can be madewithout departing from its essence and therefore these are to beconsidered to be within the scope of the following claims.

What is claimed is:
 1. A tissue spacer implant system, the systemcomprising: an implant; an insertion tool coupled to the implant; and alocking instrument.
 2. The system of claim 1, wherein the insertion toolcomprises: a housing with a first end and a second end; a handle coupledto the first end of the housing; an insertion mechanism coupled aninterior of the housing and extending from the second end of the handlethrough a length of the housing.
 3. The system of claim 2, wherein thehousing further comprises: a through hole extending from the first endto the second end and shaped to receive at least a portion of theinsertion mechanism.
 4. The system of claim 3, wherein the handlecomprises: a proximal handle portion; and a distal handle portion havinga first opening at a first end and extending into a portion of thedistal handle portion along a longitudinal axis, wherein at least aportion of the proximal handle portion engages the first opening of thedistal handle portion.
 5. The system of claim 4, wherein the handlefurther comprises: at least one fastener, the at least one fastenersecures the proximal handle portion to the distal handle portion.
 6. Thesystem of claim 4, wherein the distal handle portion further comprises:a second opening at a second end and extends into the distal handleportion along the longitudinal axis, wherein the second opening receivesa portion of the housing and a portion of the insertion mechanism. 7.The system of claim 6, wherein the proximal handle portion comprises: athrough hole extending from a first end to a second end along alongitudinal axis of the proximal handle portion, wherein a positioningmechanism of the system may extend through the through hole of theproximal handle portion, through the first and second opening of thedistal handle portion, and through the insertion mechanism; and anopening positioned perpendicular to the through hole and extending froman exterior surface of the proximal handle portion into the throughhole; wherein the opening receives an actuation button of the handle. 8.The system of claim 2, wherein the insertion mechanism comprises: aproximal end; a distal end; a threaded portion at the proximal end,wherein the threaded portion couples to an interior portion of thehandle; an opening extending from the proximal end to the distal endalong a longitudinal axis; and an engagement channel positioned on thedistal end for engagement of an exterior surface of the implant.
 9. Thesystem of claim 2, wherein the insertion tool further comprises: apositioning mechanism configured to engage an interior of the insertionmechanism and to extend through the length of the housing.
 10. Thesystem of claim 9, wherein the positioning mechanism comprises: a shaftwith a proximal end and a distal end; a knob coupled to the proximal endof the shaft; and a plurality of gear teeth at the distal end of theshaft.
 11. The system of claim 10, wherein the plurality of gear teethengage a plurality of gear structures in the implant.
 12. The system ofclaim 10, wherein the positioning mechanism further comprises: a channelpositioned near the proximal end of the shaft.
 13. The system of claim12, wherein an actuation button of the handle engages the channel. 14.The system of claim 1, wherein the locking instrument comprises: a shaftwith a proximal end and a distal end; a knob coupled to the proximal endof the shaft; and an engagement end at the distal end of the shaft. 15.The system of claim 14, wherein the engagement end engages the implantto secure the implant in a deployed position.
 16. The system of claim14, wherein the engagement end includes a multi-lobed shape.
 17. Thesystem of claim 1, wherein the implant comprises: a first cylindricalbody including an outer surface, an axially extending hole, and a firstend; a second cylindrical body including an outer surface and an axiallyextending hole; an adjustment member including an outer surface, anaxial hole extending from a first end to a second end, and at least onediagonal slot extending partially around the outer surface of theadjustment member, wherein the axial hole of the adjustment member isadapted to receive the first cylindrical body and the adjustment memberis configured to be inserted into the axially extending hole of thesecond cylindrical body; and a first travel mechanism engaging the firstcylindrical body, the adjustment member, and the second cylindrical bodyalong the at least one diagonal slot of the adjustment member tomaintain a space between two bodies of tissue.
 18. The system of claim17, wherein the adjustment member further comprises: a circularcross-section and gear structures positioned at an end of the adjustmentmember.
 19. The system of claim 18, wherein the insertion tool engagesthe gear structures of the adjustment member and the adjustment memberengages the first cylindrical body and the second cylindrical body tomove the implant to a deployed position.
 20. The system of claim 19,wherein the locking instrument engages the first travel mechanism tosecure the first cylindrical body, the second cylindrical body, and theadjustment member in a locked position.